Where is Lake Casitas?

Lake Casitas is a lake in Ventura County, California. Its water-quality measurements are published by SWRCB and shown on this page as reported.

Are there campgrounds on Lake Casitas?

Lake Casitas has 3 public campgrounds from USGS The National Map within 5 km, including Lake Casitas Recreation Area, Foster Residence Campground, Foster Red Mountain Campground. This is a location join, not a booking. Cabins and hotels are listed separately; campsite reservations use the official link when the source provides one.

Lake Casitas

Ventura County, California1,540 acresView map Directions

No nutrient or algae sampling on record from SWRCB for this lake.

Area

1,540 acres

Surface area

Impaired · Mercury
Limited data

See the measurements Directions Where to stay

Lake Casitas in Ventura County, California has water-quality measurements published by SWRCB, shown here as reported. Surface area: 1540 acres.

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Lake Casitas is a 1,540-acre lake in Ventura County, California.

Source: EPA Water Quality Portal sampling records, your state environmental agency. Methodology: how these readings are compared.

What Lake Casitas is good for

From access and monitoring records, not editorial picks.

Camping3 public campgrounds nearby
Big water1,540 acres

Swimming conditions

No reading

Limited data

Nutrient and algae readings are not a swimming clearance. Lake Casitas is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.

Whether Lake Casitas is safe to swim in today is a call for the California State Water Resources Control Board and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for Lake Casitas

These are the measurements SWRCB publishes for Lake Casitas, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.

No clarity data.

Ask about Lake Casitas

Answers come straight from the public measurements and survey records on this page.

Lake Details

Surface area

1,540 acres

No bathymetric survey has been published for Lake Casitas, so its depth is not documented here.

Recreation & Access

Campgrounds

Public campgrounds near Lake Casitas

Lake Casitas Recreation Area2.9 km
Foster Residence Campground4.2 km
Foster Red Mountain Campground4.8 km

Nearest public campgrounds in the USGS National Map inventory, within about 3 miles. An empty list means USGS records no campground that close, which is not the same as camping being unavailable. Where the source gives an official reservation link, it is used; the cabin and hotel search does not cover campsites. More camping lakes

Stays via Stay22

Stays near Lake Casitas

Compare lakeside cabins, hotels, and vacation rentals near Lake Casitas in Ventura County, California — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.

Top-rated places to stay near Lake Casitas

Prices for Oct 9–11, 4 adults. Change dates on the map below.

Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.

Follow Lake Casitas’s readings

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Fishing Lake Casitas

→ Lake Casitas fishing regulations (limits, seasons, special rules)

EPA Impairment Status

Lake Casitas is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).

Causes of impairment

Mercury

Designated uses not supporting: Fish consumption, Other.

Source: EPA ATTAINS assessment unit CAL4022003220091208111831 · Official waterbody report

Nearby Lakes in Ventura County

Matilija Lake6.9 miView →Lake Sherwood31.8 miView →Wood Ranch Reservoir31 miView →Lake Piru—View →

Frequently asked questions about Lake Casitas

Where is Lake Casitas?: Lake Casitas is a lake in Ventura County, California. Its water-quality measurements are published by SWRCB and shown on this page as reported.
What is the water quality of Lake Casitas?: Lake Casitas in Ventura County, California has water-quality measurements published by SWRCB, shown here as reported. Surface area: 1540 acres.
Is Lake Casitas safe to swim in?: Nutrient and algae readings are not a swimming clearance. Lake Casitas is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
Are there campgrounds on Lake Casitas?: Lake Casitas has 3 public campgrounds from USGS The National Map within 5 km, including Lake Casitas Recreation Area, Foster Residence Campground, Foster Red Mountain Campground. This is a location join, not a booking. Cabins and hotels are listed separately; campsite reservations use the official link when the source provides one.